This section provides background information related to the present disclosure which is not necessarily prior art.
Conventional, hermetically-sealed, electric power terminal feed-throughs (also referred to as “hermetic terminals”) provide an airtight electrical terminal for use in conjunction with hermetically sealed devices, such as A/C compressors, where leakage into or from such devices, by way of the terminals, is effectively precluded. For hermetically-sealed electric power terminal feed-throughs to function safely and effectively for their intended purpose, the hermetic terminals require that their conductor pins be electrically isolated from, and hermetically sealed to, the body of the terminal through which they pass. In addition, an optimum through-air path between adjacent portions of the pins the opposite sides of the body, as well as between the pins themselves, must be established and thereafter maintained to minimize the possibility for generating an electrical short circuit at the terminal.
An exemplary hermetic terminal 1 and associated connector block 2 having constructions that are well-known in the art are shown in FIGS. 1-4. In such conventional hermetic terminals 1, an electrically conductive pin is fixed in place within an aperture through a metal body by a fusible sealing glass that forms a hermetic, glass-to-metal seal between the pin and the terminal body.
A resilient electrical insulator is bonded to the outside surface of the body, as well as over the glass-to-metal seal and portions of the current-conducting pins. The insulator provides a dielectric over-surface covering for substantial portions of the outside surface of the terminal body and the conductor pins. In doing so, the insulator increases a path through the air between adjacent non-insulated portions of the conductor pins and the terminal body (though not between the pins in their entirety) and reduces the ability for contaminants, debris, and the like (e.g., metal shavings) to form unwanted current paths that could create an electrical short circuit at the terminal between the pin and the body.
Optionally, a connector block 2 like that shown in FIGS. 2, 3A and 3B may be used in conjunction with the hermetic terminal 1. As illustrated in FIGS. 3A and 3B, the connector block 2 cooperatively engages with the ends of the plurality of conductor pins of the hermetic terminal 1 and provides a mounting fixture for attaching to the hermetic terminal lead wires that can be electrically connected to a power source disposed on one side of the hermetic terminal 1.